Infineon Technologies CY2544QC011T

Overview

CY2544QC011T from Cypress Semiconductor is a quad-PLL programmable clock generator with spread spectrum capability, designed for high-precision timing synthesis in multi-clock domain systems. It delivers up to nine LVCMOS clock outputs (3–166 MHz), supports 1.8 V input reference and 2.5/3.0/3.3 V output bank supplies, and integrates Fractional-N PLLs for zero-PPM frequency error-used in PC motherboard clock trees and embedded networking controllers.

For engineers reviewing the CY2544QC011T datasheet, CY2544QC011T pinout, CY2544QC011T application, or CY2544QC011T equivalent, key selection criteria include its four independent PLLs, per-bank voltage-selectable outputs (1.8 V/2.5 V/3.0 V/3.3 V), glitch-free frequency switching via FS0–FS2, spread spectrum modulation (Lexmark/Linear, ±0.125% to ±2.5%), and 24-pin QFN package compatibility with industrial temperature range operation.

Technical Context

The CY2544QC011T implements four fully configurable PLLs-PLL1 through PLL4-with PLL3 and PLL4 supporting spread spectrum modulation for EMI reduction. Input reference options include an 8–48 MHz crystal (XIN/EXCLKIN) or 8–166 MHz external clock (CLKIN), both at 1.8 V logic level.

Outputs are grouped into three independently powered banks (Bank1: CLK1–CLK3; Bank2: CLK4–CLK6; Bank3: CLK7–CLK9), each configurable for 1.8 V, 2.5 V, 3.0 V, or 3.3 V drive. Frequency selection uses three multifunction pins (FS0–FS2) to choose among eight preprogrammed frequency sets, while PD#/OE (Pin 4) enables power-down or output-enable control.

Key Specifications

Pinout & Package

24-pin QFN (4 mm × 4 mm, 0.5 mm pitch) with exposed thermal pad; pin-compatible across CY2544/CY2546/CY2548 family. Power and ground pins distributed for low-noise clock distribution and EMI mitigation.

Key Features

Applications

Equivalent & Alternatives

CY2544QC011T alternatives provide comparable quad-PLL functionality with trade-offs in voltage support, spread spectrum flexibility, or package options.

Compared with Si5338A-D-GM and ICS8430I-01LFT, CY2544QC011T uniquely combines nine programmable outputs, per-bank voltage control, dual-spread-spectrum PLLs, and one-time programmability-making it optimal for complex, EMI-sensitive, multi-voltage embedded systems requiring field-configurable timing.

Availability

CY2544QC011T is available at Aetrix Electronics and suitable for PC motherboard design, industrial PLC timing, embedded media gateway development, and networking switch ASIC synchronization requiring stable component supply and long-term lifecycle support.

Supply support for CY2544QC011T includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Cypress Semiconductor (now part of Infineon Technologies) designs high-performance timing, memory, and microcontroller solutions for industrial, automotive, and computing applications.

CY2544QC011T belongs to the CY254x Quad-PLL Clock Generator family, engineered to replace multiple fixed-frequency oscillators with a single programmable device capable of synthesizing precise, low-jitter clocks for complex multi-domain systems.

FAQ

What is the function of the PD#/OE pin (Pin 4) on CY2544QC011T?

Pin 4 is a multifunction control input that can be configured either as active-low Power-Down (PD#) or Output Enable (OE). In PD# mode, asserting low shuts down all PLLs and outputs, reducing current to <10 µA. In OE mode, it globally enables or disables all clock outputs without affecting PLL lock state-enabling dynamic power gating in real-time systems.

Can CY2544QC011T generate non-integer output frequencies?

Yes. The device uses Fractional-N PLL synthesis to achieve exact non-integer multiples of the input reference (e.g., 100.125 MHz from a 25 MHz crystal), eliminating cumulative timing error. This capability is factory-programmed or user-configured via one-time programming and enables zero-PPM frequency accuracy critical for high-speed serial interfaces like PCIe and SATA.

How does spread spectrum work on CY2544QC011T, and which PLLs support it?

Spread spectrum modulation is implemented exclusively on PLL3 and PLL4 using Cypress's proprietary SSC engine. It applies controlled frequency dithering (center-spread ±0.125–2.5% or down-spread –0.25–5.0%) with Lexmark or Linear profiles. Modulation is enabled/disabled via CLK7/SSON (Pin 15), allowing selective EMI reduction on specific clock domains without affecting others.

Is CY2544QC011T pin-compatible with CY2546 or CY2548 variants?

Yes-CY2544QC011T shares identical 24-pin QFN pinout and footprint with CY2546 and CY2548. Differences lie in voltage support: CY2544QC011T accepts 1.8 V reference input and 2.5/3.0/3.3 V VDD, while CY2546 uses 1.8 V only and CY2548 omits crystal support. PCBs designed for one variant can accommodate others with minor power routing adjustments.